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1.
B. Itier D. Flura K. Belabbes P. Kosuth G. Rana L. Figueiredo 《Irrigation Science》1992,13(3):109-114
Summary The measurement of water consumption in the field is normally restricted to research purposes, although the development of practical field criteria for timing water application is required to improve crop productivity. To develop such criteria irrigation experiments on Soybean were conducted from flowering to grain filling at four locations which differed in their soil properties and the convective contribution of their climates to potential evapotranspiration. The energy balance, predawn leaf water potential (PLWP), soil moisture depletion, and a crop water stress index (CWSI) based on foliage temperature were measured. The range of soil, atmospheric, phenological and irrigation conditions, produced a common, linear relation between relative evapotranspiration (rET) and the logarithm of -PLWP. Correlation with the temperature based CWSI was weak. A similar relation with PLWP for other C3 plants was also derived from data in the literature. This relation could be helpful for irrigation scheduling once the critical values of rET for crop productivity are known. 相似文献
2.
A field experiment was conducted with a bunched variety of peanut (Arachis hypogaea L.) cv. JL-24 during the summer seasons (March–June) of 1992 and 1993 in the humid tropical canal command area at the University Experimental Farm, Memari (23°1 N, 88°5 E and 21.34 m a.s.l) in West Bengal of eastern India. The soil at the site is of sandy loam (Typic Fluvaquent) texture and the area has a shallow water table. Weekly and seasonal field water balance components of actual evapotranspiration (ETa) including the capillary contribution into root zone were determined. Peanut yield and water productivity were determined for three ratios of irrigation water and cumulative pan evaporation (CPE) of 0.9, 0.7 and 0.5. Mean crop coefficients were determined for each 7-day period of growth and were related to leaf area index and growing degree-days. Average seasonal values of ETa of peanut were 434, 391 and 356 mm for the three treatments, respectively, for 115 days of growth. The total pod yield and WP were significantly higher in 0.9 IW:CPE treatment in the 1992 season. On an average, 0.9 IW:CPE treatment had 7 and 11% higher yields in 1992 and 1993, respectively, over treatments 0.7 and 0.5 IW:CPE. The maximum average Kc of 1.19 occurred about 9 weeks after sowing relative to grass reference ET (ETo). 相似文献
3.
Improved protocol for Agrobacterium mediated transformation of tomato (Lycopersicon esculentum) Micro-Tom was developed to use in corporation of the carotenoid biosynthetic genes CsZCD (Crocus zeaxanthin 7,8-cleavage dioxygenase). From these experiment, a transformation methodology using explants from cotyledons cultured for 1 day on the medium with zeatin 2 mg/L, IAA 0.1 mg/L, carefully submerged in the Agrobacterium inoculum for 20 min, then concultured with the agrobacterium for 3 days on the same medium, followed by a transfer to the same medium with 500 mg/L cefotaxin for 3 days and then by a transfer to the same medium with 100 mg/L kanamycin and 500 mg/L carabenillin for 6–8 weeks and resulted in a greater than 20% transformation efficiency in the concentration of Agrobacterium OD600 = 0.2 tested. In this transformation method, no feeder layers were used and the subculture media was minimal. Among the Agrobacterium concentrations of OD600 = 0.2, 0.5 and 1.0, the best transformation efficiency, 20.87%, was obtained by using OD600 = 0.2, which was significantly higher than that of OD600 = 1.0. The presence of the inserted target genes was checked using a rapid and efficient PCR test. The protocol was successfully employed in the production of transgenic Micro-Tom tomato containing the carotenoid biosynthesis CsZCD under constructive promoter. This procedure represents a simple, efficient and general means of transforming tomato. 相似文献
4.
The effect of ethanolic extract of the roots of Calotropis procera has been studied in albino rats to explore its antifertility and hormonal activities. A strong antiimplantation (inhibition 100%) and uterotropic activity was observed at the dose level of 250 mg/kg (1/4 of LD(50)). No antiestrogenic activity could be detected. 相似文献
5.
Milena Bordignon Laura Da Dalt Lieta Marinelli Gianfranco Gabai 《Veterinary journal (London, England : 1997)》2014,199(1):162-168
Despite the recognised importance of oxidative stress in the health and immune function of dairy cows, protein oxidation markers have been poorly studied in this species. The current study aimed to characterise markers of protein oxidation generated by activated bovine neutrophils and investigate the biological effects of advanced oxidation protein products (AOPP) on bovine neutrophils. Markers of protein oxidation (AOPP, dityrosines and carbonyls) were measured in culture medium containing bovine serum albumin (BSA) exposed to neutrophils. The effect of AOPP-BSA on generation of reactive oxygen species (ROS) was assessed by chemiluminescence. Activation of caspases-3, -8 and -9 and the presence of DNA laddering were used as apoptosis markers.Greater amounts of AOPP were generated by phorbol myristate acetate (PMA)-activated than non-activated neutrophils (1.46 ± 0.13 vs. 0.75 ± 0.13 nmol/mg protein, respectively; P < 0.05). Activated neutrophils and hypochlorous acid generated slightly different patterns of oxidized protein markers. Exposure to AOPP-BSA did not stimulate ROS production. Activated neutrophils generated a lesser amount of ROS when incubated with AOPP-BSA (P < 0.001). Activation with PMA induced a loss of viable neutrophils after 3 h, which was greater with AOPP-BSA incubation (P < 0.05). Detectable amounts of active caspases-3, -8 and -9 were found in nearly all samples but differences in caspase activation or DNA laddering were not observed comparing treatment groups. Apoptosis was unlikely to be responsible for the greater loss of PMA-activated neutrophils cultured in AOPP-BSA and it is possible that primary necrosis occurred. The results suggest that accumulation of oxidized proteins at an inflammatory site might result in a progressive reduction of neutrophil viability. 相似文献
6.
Growth response and survival of catfish, Heteropneustes fossilis, fed compounded pelleted diet have been studied. It was observed that the fish accepts and thrives well on pelleted feed, with 100% survival. The conversion factor of the feed over a 6-week feeding trial was found to be 1.8, corresponding to gross growth efficiency of 0.56. The study suggests that cost-effective raw materials could be used for compounding nutritive feed for this species. 相似文献
7.
Morphological development of post hatch larval goldlined seabream Rhabdosargus sarba (Forskål, 1775)
Fahad S Ibrahim Krishen J Rana James Stephen Goddard & Issa S Al Amri 《Aquaculture Research》2006,37(12):1156-1164
Ultrastructural changes in Rhabdosargus sarba larva in early life history were investigated. At hatching, the digestive system was histologically undifferentiated. The digestive tract was a straight tube attached to the dorsal end of the yolk‐sac and was not connected to either the mouth or the anus. The layer of gut epithelium at some regions of the luminal surface was straight and microvilli were not present. These straight borders were not observed at 1 day post hatching (DPH) onwards as microvilli increased in number on the luminal surface and became more regular. At 2 DPH, the digestive system was well differentiated and the separation of the mid‐ and hindgut by the intestino‐rectal valve became more advanced. At 0 DPH, the eye was spherical and the retina had a zonation with undifferentiated cells. The eye also lacked differentiated photoreceptors (PR). The retinal PRs increased in length and in number as the yolk‐sac was absorbed. By 2 DPH, the eye was fully pigmented, suggesting that the larval vision system was functional. The larvae had a pure cone retina at the onset of exogenous feeding. Morphological and functional differentiation of the digestive tract and the eye of the larvae preceded the completion of yolk and oil globule absorption. The oil globule was exhausted at 4 DPH and at 2 DPH, the yolk‐sac was completely absorbed. Food particles were observed at 3 DPH. Food particle ingestion and absorption of the yolk‐sac were observed as vision became fully functional. 相似文献
8.
9.
Kripal Singh Ashish Kumar Mishra Bajrang Singh Rana P. Singh Dharani Dhar Patra 《Land Degradation \u0026amp; Development》2016,27(2):223-230
Tillage modifies soil structure and has been suggested as a practice to improve physical, hydrological and chemical properties of compacted soils. But little is known about effect of long‐term tillage on physicochemical soil properties and crop yield on sodic soils in India. Our objective was to investigate the effect of different tillage regimes on crop yield (wheat and paddy rice) and physicochemical properties of sodic soils. Two sodic sites under conventional tillage for 5 (5‐YT; 5‐year tillage) and 9 (9‐YT; 9‐year tillage) years were selected for this study. Changes in crop yield and physicochemical soil properties were compared with a control, sodic land without any till history, that is, 0‐year tillage/untilled (0‐YT). Five replicated samples at 0‐ to 10‐cm and 10‐ to 20‐cm soils depths were analysed from each site. In the top, 0‐ to 10‐cm soil depth 5‐YT and 9‐YT sites had higher particle density (Pd), porosity, water holding capacity, hydraulic conductivity, organic carbon, total nitrogen (Nt), available nitrogen (Navail), phosphorus (Pavail) and exchangeable calcium (Exch. Ca++) than 0‐YT, whereas bulk density (Bd), C : N ratio and CaCO3 were significantly lower. Bd, pH, EC and CaCO3 increased significantly with depth in all the lands, whereas Pd, porosity, water holding capacity, hydraulic conductivity, organic carbon, Nt, Navail, Pavail and Exch. Ca++ decreased. We conclude that continuous tillage and cropping can be useful for physical and chemical restoration of sodic soils. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
10.
An analysis was made of the stomatal apparatus of the leaves of five Italian durum wheat varieties, grown under different natural rainfall regimes.Rainfall had a significant influence on both development of the leaves and frequency and size of the stomata. Results were examined with respect to yield stability. Correlations between examined traits were calculated. 相似文献